鼠李糖乳杆菌LT22发酵培养基优化

目的]提高发酵液中鼠李糖乳杆菌LT22的菌体浓度。方法]采用Plackett-Burman设计对培养基中相关影响因素的效应进行评价,筛选出3个重要因素依次为葡萄糖、酵母膏和吐温80;然后进行最陡爬坡试验逼近最佳响应面区域;最后通过Box-Behnken设计及响应面分析法确定最佳培养基配方。结果]鼠李糖乳杆菌LT22的最佳培养基配方为:葡萄糖17 g、蛋白胨12 g、牛肉浸膏10 g、酵母膏4.8 g、乙酸钠3 g,柠檬酸氢二铵2 g、MnSO4.H2O 0.1 g、MgSO4.7H2O 0.6 g、吐温80 0.6 ml、蒸馏水1 000 ml。用优化培养培养鼠李糖乳杆菌,其发酵液的菌体含量是MRS培养的6.7倍。结论]结果为鼠李糖乳杆菌动物微生态制剂的研制奠定了基础。

Optimization of the Growth Medium for a Lactobacillus rhamnosus LT22 Strain

Objective] To improve the concentration of Lactobacillus rhamnosus LT22 in the fermentation broth.Method] The effect of Plackett-Burman design on the influence factors of the medium was evaluated,and the three important factors were glucose,yeast extract and Tween 80.Then the central composite design and response surface analysis were used to determine the optimal levels of the important factors.Result] The best culture medium for Lactobacillus rhamnosus LT22 were 17 g glucose,12 g peptone,10 g beef extract,4.8 g yeast extract,3 g CH3COONa,2 g diammonium hydrogen citrate,0.1 g MnSO4·H2O,0.6 g MgSO4·7H2O,0.6 ml Tween 80 and 1 000 ml H2O.The amount of Lactobacillus rhamnosus LT22 cultured by the optimized culture medium was 6.7 times that cultured by MRS.Conclusion] The results lay foundation for the animal microecological preparation of Lactobacillus rhamnosus LT22.